The Red-legged Frog (Rana aurora)

     The Red-legged Frog is found all over Vancouver Island, the Gulf Islands and the adjacent mainland coast of British Columbia. It ranges south down to the very northern tip of California, in the coastal lowlands west of the Cascades mountains.

Photograph of Red-legged Frog
Photograph by S.Price

  • Red-legged Frogs are 5 to 7 cm long.

  • They are reddish brown on top with small, irregular black spots.

  • Raised folds of skin on the back called dorsolateral folds are a lighter shade of brown.

  • The arms and legs are marked with dark bands.

  • The flanks in the groin area are tinged light green and mottled with black markings.

  • The undersides of the hind legs and belly are a deep, rich red. This colour is much darker in older frogs.

Comparison of a Red-legged Frog and a young Bullfrog
Photograph by S. Price

Habits: Red-legged Frogs are found in forested habitats, in cool, well shaded ponds and lakes. They sometimes wander away from standing water into the cool damp forest floor to forage. Red-legged frogs mainly eat insects and other small invertebrates.
Breeding: Red-legged Frogs are the first to breed in our area, and may start as early as mid-February when air temperatures are still below zero at night but water temperatures are about 5 degrees C. Red-legged Frogs are unique in that their mating calls are only heard under water. This  Red-legged Frog breeding call   was recorded in Prior Lake in Victoria using a hydrophone.


Eggs are laid under water and the eggmass is the size of a cataloupe melon. The eggs are dark above and light coloured below and surrounded by a thick layer of soft jelly. Often, there is green algae growing inside the egg mass, forming a cocoon around each embryo.

Red-legged Frog egg mass
Photograph by S. Price

Red-Legged Frog tadpole
Photograph by S. Price

The tadpoles are stubby, with a high dorsal fin. The mouth has three tooth rows on top and four on the bottom. The larger tadpoles are dark brown with black splashes on the tail.


Tadpoles metamorphose into small froglets (2 cm long) in mid to late summer. It will be two or three year before they are large enough to breed.

Red-legged Frog metamorph
Photograph by J. Parmley

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Webpage written and maintained by Purnima Govindarajulu and Mike Dodd
email: bcfrogwatch@victoria1.gov.bc.ca
Last updated May 2008